• U.S.

Medicine: Ragweed Fallacy

1 minute read
TIME

The promiscuous sexual life of the giant ragweed (Ambrosia trifide)and other species again last week brought tears to the eyes of several million U.S. hay fever sufferers. In the next few weeks a good million tons of ragweed pollen will drift imperceptibly over the U.S. seeking mates.

Meanwhile an army of 4,000 men has for several weeks been uprooting ragweed in New York City, where it is now a legal offense to let the weed grow. Similar campaigns are under way in other towns.

Chicago could have told New York that it is wasting its time. In 1933 Chicago put 25,000 men to work cleaning up weeds (cost: $165,000). Result: no lessening in pollen concentrations, sneezes & sniffles. Reason: ragweed that grows within city limits is only an infinitesimally small source of hay fever infection. The main source is pollen carried by the wind over some 2,000,000 square miles where ragweed flourishes east of the Rockies.

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